Electrification of water: From basics to applications

As the most common but indispensable matter to humankind, water usually stays in a macroscopically electric neutral state. Due to its inherent molecular polarity, however, water can be easily electrified, which builds a connection between water and electricity. Such a coupling of water and electricity abounds deep scientific basics and technological applications. The past several decades have witnessed extensive progress in studying the mutual effects between electricity and water, but a comprehensive review of its fundamentals and applications is still largely missing. In this review, we first reassess and classify the basic electrifying methods of water according to their mechanisms, then highlight how to leverage the bond nexus of water and electricity to achieve promising technical applications. We envision that this review will inspire multidisciplinary scientific communities to think and innovate more on the research of water, electricity, and their marriage.